John Gill Commentary Exodus 30:37

"And the incense which thou shalt make, according to the composition thereof ye shall not make for yourselves: it shall be unto thee holy for Jehovah." — Exodus 30:37 (ASV)

And [as] for the perfume which you shall make
As above directed:

you shall not make for yourselves according to the composition
thereof ;
that is, for their own use, for the scenting of their rooms, or to snuff up, or smell to, as in the next verse:

it shall be to you holy for the Lord ;
separated entirely for his service, to be burned upon his altar, and to be no otherwise used.